Robot is 3D-printed upside-down in one piece, then walks out of the printer

Summary

While there are many potential uses for soft-bodied robots, the things are still typically only built in small experimental batches. Scottish scientists are out to change that, with a mass-production-capable soft bot that is 3D-printed in a single piece which then walks off of the print bed.Before we go any further, this isn't the first time we've heard about a soft robot that was printed in one piece.It was just this March that we told you about a hexapod bot created at UC San Diego, which was 3D-printed in one continuous 58-hour step. That robot was powered not by a motor but by compressed air, which sequentially moves its legs forward.The new quadruped robot, designed by scientists at The University of Edinburgh, is likewise air-driven.Unlike the UC San Diego bot, however, it "only" takes nine hours to print. What's more, whereas the San Diego robot was made using a US$1,000 printer, the Edinburgh bot is made by a ~$500 open-source platform called the Flex Printer, which is constructed from off-the-shelf components. The Flex Printer is open-source and consists of off-the-shelf componentsThe University of Edinburgh Like its American predecessor, the Scottish robot is printed entirely out of soft, flexible thermoplastic polyurethane (TPU). That material starts out as a filament which is heated to the melting point, then extruded out of a print nozzle to build up the robot's body in successive layers.Because the molten TPU is so soft, however, it's notoriously difficult to work with. For one thing, instead of lying in nice straight (or curved) lines when being extruded, it has a tendency to buckle off to one side or the other. The scientists describe the extrusion process as being like "trying to push on a piece of string."Additionally, before the molten TPU cools back to a firmer (yet still elastic) consistency, the force of gravity causes it to droop. This is particularly problematic when printing horizontally suspended bridge-like structures, as the drooping acti...